stylophone

Judging from the video (found after the break) the Nebulophone is one of the best sounding DIY synthesizers we’ve seen. Especially when you consider the simplicity of the hardware design. It uses an AVR chip and an OpAmp. The rest of the parts are just a few handfuls of inexpensive components.

An ATmega328 drives the device, which is the chip often used in the Arduino Duemilanove. The keyboard is a set of traces hooked to the microcontroller. These are tinned pads on the kit PCB, but the DIY version simply uses some adhesive copper foil with a jumper wire soldered to it. The keys are played with a probe that makes the electrical connection, a common practice on these stylophone type designs. Chances are you have everything on hand to make this happen so keep it in mind for that next cold winter weekend that’s making everyone a bit stir crazy.

The Stylophone – a musical toy from the 60s – is a surprisingly simple piece of engineering. With a simple metallic keyboard played with a stylus and just a handful of transistors, the Stylophone was able to produce a few marvelous for their time sounds, and is the equivalent of a pre-[Stradivarius] violin for the electronic music scene. [Simon] tore apart an original Stylophone, and did a complete teardown of the circuit, going over the ins and outs of why this ancient noise box is so cool.

There have been quite a few DIY Stylophone clones, but all of them suffered from the same raspy sound made by a 555 timer chip slightly misguided makers used instead of the relaxation oscillator (in the pic seen above) used in the original. Aside from the oscillator connect to the RC circuit of the metallic keyboard, [Simon] also looked into the vibrato circuit. This is just a simple oscillator producing an 8 Hz sine-ish wave. The keyboard, of course, is connected to the circuit with an array of resistors which [Simon] happily provided the values for.

[Simon] put up a schematic of his reverse engineered Stylophone, allowing you to clone this ancient electronic instrument. If you can source the transistors, that is.

We love looking in on [Simon Inns’] projects, and this must be one of his very best. This is the fifth version of his MIDI-capable stylophone. The gist of the control system is that a conductive keyboard (made of a tinned PCB) is played by making a connection with the tip of a wired stylus — hence the name. The idea comes from the original 1968 Dubreq Stylophone hardware, but [Simon’s] not just using the idea. He has his own working original and used it to reverse engineer the circuit design.

When it first came out, the Stylophone had three flavors for Bass, Standard, and Treble audio ranges. They differed only in the choices of passive components used in the circuit. [Simon] built the variations into his design so that they are selectable on one unit. This most recent version connects via USB, allowing you to control MIDI software. But unlike his first four iterations, this also offers MIDI-In capabilities. This makes it possible to control tuning, vibrato, and to drive the Stylophone circuitry from the computer interface. Get a good look at that, and a nostalgic Portal moment, by watching the clip after the break.

[Doug Jackson] just finished building an analog Stylophone. We’ve seen this instrument a few times before, most recently with an Arduino-based controller, but this one makes use of 555-timer, resistors, and potentiometers to generate the waveform for each note. If you’ve got the copper-clad and the means to etch the board everything else should be pretty easy to come by. We did note that since this is a single-sided board you’ll be soldering on the same side as the components, which can get a bit hairy but manageable. We just wish that [Doug] has posted a demonstration video so we could hear what this sounds like. But it can’t be too much different from that electronic vuvuzela that used a 555 timer as well.